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31.
Ohne Zusammenfassung
Spectrophotometric determination of bovine serum albumin with 5-isothiocyanato-1,3-dioxo-2-p-tolyl-2,3-dihydro-1h-benzo[de]isoquinoline相似文献
32.
33.
Preparation and synthetic applications of 2-halotryptamines: synthesis of elacomine and isoelacomine
The preparation of 2-halotryptamines from tryptamine is described. New stereoselective intramolecular iminium ion spirocyclization methodology for the construction of spiro[pyrrolidine-3,3'-oxindoles] is outlined in synthetic studies of elacomine (1) and isoelacomine (2). [reaction: see text] 相似文献
34.
Fumiko Akagi Masaki MukohMasafumi Mochizuki Junko UshiyamaTakuya Matsumoto Harukazu Miyamoto 《Journal of magnetism and magnetic materials》2012,324(3):309-313
Thermally assisted magnetic recording (TAR) with bit-patterned media was investigated by micromagnetic simulation. The media were assumed to be FePt layers. The effective head-field margin as well as the increase in temperature margin and down-track shift margin was investigated. Conditions of the head and medium that lead to a recording density beyond 5 Tb/in2 were proposed. 相似文献
35.
Fumiko MITANI 《Proceedings of the Japan Academy. Series B, Physical and biological sciences》2014,90(5):163-183
The adrenal cortex of mammals consists of three concentric zones, i.e., the zona glomerulosa (zG), the zona fasciculata (zF), and the zona reticularis (zR), which secrete mineralocorticoids, glucocorticoids, and adrenal androgens, respectively. In 1994, we identified immunohistochemically a new zone between zG and zF of the rat adrenal gland. The zone appeared to be devoid of any significant endocrine functions specific to adrenocortical zones, therefore, we designated the zone as “undifferentiated cell zone (zU)”. Further, BrdU (5-bromo-2′-deoxyuridine)-incorporating cells (cells in S-phase) were concentrated at the outer region and the inner region of zU, and these cells proliferated and migrated bidirectionally: toward zG centrifugally and toward zF centripetally. We proposed that cells in and around zU are stem/progenitor cells of the rat adrenal cortex, maintaining functional zonation of the adrenal cortex. The view is consistent with observations reported recently that Sonic hedgehog (Shh), an important factor in embryonic development and adult stem cell maintenance, exists in zU of the rat adrenal gland and the Shh-containing cells seem to migrate bidirectionally. 相似文献
36.
Abstract We present the results of constant pressure molecular dynamics simulation under hydrostatic pressure for soft parallel spherocylinders. A clear first order transition from crystal to smectic phase is observed. The anisotropy of the molecular volume plays an important role in this transition. We study the anisotropy of the diffusion process in the smectic phase by the mean-square displacement in each direction. Also the structures before and after the transition are analysed by means of the pair distribution functions. 相似文献
37.
Hiroshi Fukuoka Kazuya Baba Mayumi Yoshikawa Fumiko Ohtsu Shoji Yamanaka 《Journal of solid state chemistry》2009,182(8):2024-2029
A series of lanthanide penta-germanides LnGe5 (Ln=Ce, Pr, Nd and Sm) has been prepared by high-pressure (5–13 GPa) and high-temperature (500–1200 °C) reaction. CeGe5 crystallizes in an orthorhombic unit cell (S.G. Immm (71)) with a=4.000(5) Å, b=6.192(5) Å, c=9.86(1) Å, and V=244.1(5) Å3. The new germanides are isotypic with LaGe5 consisting of a Ge covalent network with tunnels where guest ions Ln3+ are situated. The network is composed of sublayers with edge-sharing Ge six-membered rings with only boat conformation. The sublayers are connected by rare eight-coordinated Ge atoms. The cell volume of the compounds systematically decreases from La to Sm compounds, except for CeGe5, owing to the lanthanide contraction. The lattice constants of CeGe5 are smaller than those of the Pr compound because it contains Ce4+ ions. CeGe5 is paramagnetic above 2 K, but does not obey the Curie–Weiss law. PrGe5 and NdGe5 are Curie–Weiss type paramagnets with Weiss temperatures of –3.3 and –18.4 K. SmGe5 shows an antiferromagnetic transition at 10.4 K. 相似文献
38.
Keiichi Sakashita Tetsuya Ikemoto Yuriko Nakaoka Shigeo Kamimura Yoshitaka Kageyama Fumiko Terada Yoshihiro Sako Kenji Mori 《Liquid crystals》1992,12(5):769-777
Both (2S, 5R)- and (2R, 5R)-2-hydroxy-5-alkyl-δ-valerolactone derivatives, cis and trans, respectively, show almost the same magnitude of spontaneous polarization (Ps) when added to a non-chiral smectic C mixture. The stereochemistry of these chiral dopants was studied using 1H NMR. Trans derivatives seem to have a half-chair conformation with the 2, 5-diequatorial substituents and the cis derivatives have rather a flat conformation in solution. However in the liquid-crystalline phase, the cis and trans derivatives appear to change their conformation or the distribution of their conformations as the alkyl chain length is varied. The difference in the effect as a chiral dopant depends upon lateral interactions between chiral molecules through the solvent liquid crystal phase. 相似文献
39.
Takashi Kato Toshiyuki Uryu Fumiko Kaneuchi Chihiro Jin Jean M. J. Fr chet 《Liquid crystals》1993,14(5):1311-1317
The stability of a hydrogen-bonded complex built through inter-molecular hydrogen bonding between carboxylic acid and pyridine fragments has been examined using infrared spectroscopy. Infrared spectra as a function of temperature have been recorded for the 1:1 complex of 4-hexyloxybenzoic acid and trans-4-propoxy-4'-stilbazole from the crystalline state to the isotropic state. A dependence of the stability of the hydrogen bond on molecular orientation is observed clearly in the infrared spectra. The spectra also suggest that the hydrogen bond is an unionized type with a double minimum potential energy. 相似文献
40.
Tetsuya Ikemoto Yoshitaka Kageyama Fumiko Onuma Yuriko Shibuya Kiyoshi Ichimura Keiichi Sakashita Kenji Mori 《Liquid crystals》1994,17(5):729-739
A series of new optically active δ-lactones were synthesized as chiral dopants for ferroelectric liquid crystals (FLCs). The response time of an FLC mixture containing 4 mol% (S)-2,2-dimethyl-5-[2-fluoro-4-(5-n-octylpyrimidin-2-yl)-phenoxy[methyl-δ-valerolactone was 25 μs at 25°C. (0-90 per cent change in light transmission, 10 V μm-1). The synthesis and properties of these materials as practical chiral dopants are reported. 相似文献